Very often. A lot of people have cold sores, which is a form of herpes virus. Herpes is also easy to get as an STD if the person is having a break out and you can't always tell. Best thing is to use a condom at all times.
You and him get tested before you have sex. Also remember there are about 8 strains of herpes viruses, not all are STD's. Some you can even get from chicken pox.
You don't always know, unless he tells you. That's why you should never have unprotected sex.
Yes, there is a strain of herpes you can get through kissing someone.
how often is it that someone could get herpes?
and what about kissing someone?